Bird Nest Boxes in Boundary Bay Regional Park
The Delta Naturalists Society maintains about 30 Bird Nest Boxes in Boundary Bay Regional Park. These are primarily for Tree Swallows. There is also one Barn Owl box in a remote area of the park.
Twice a year, we monitor the boxes. In the Fall we open the boxes to see which ones have been used for nesting and by which species. We clean out the boxes and either leave them open or plug the openings for the winter. This is done so that rats and wasps do not use them. I n the Spring we open and repair them as necessary.
We are trying to encourage Tree Swallows, which like other insect-eating birds, are declining world-wide. This may be due to habitat loss, pesticide use, changes in insect populations and competition from non-native species like the European House Sparrow. We have tried to discourage House Sparrows by decreasing the size of the opening. Some boxes are in wooded areas to encourage use by the native Black-capped Chickadees.
We record which boxes have been used by each species. Tree swallow nests are usually neat and thin and made of grass and duck feathers. House Sparrow nests are thick and messy and made of grass and duck feathers. Chickadee nests are made of moss and hair. Some boxes have more than one nest on top of each other.
On October 6, 2016, fifteen Delta NatureKids and their parents joined some Delta Naturalists when the boxes were opened and examined. To see the photos in a slide show go to this link and then click on the small tv screen near the top right of the page.
In 2012, 15 boxes were occupied – 2 Swallow, 9 Sparrow, 2 Chickadee, 2 double (Swallow/Sparrow).
In 2013, 6 boxes were occupied – 2 Swallow, 3 Sparrow, 1 Chickadee, 25 empty. (So many were empty because baffles had been put on most to reduce the opening size so that Sparrows could not fit. Swallows must have had trouble too. Most of these were removed for the next year.)
In 2014, 16 boxes were occupied – 4 Swallow, 11 Sparrow, 1 double (Chickadee/Sparrow), 15 empty.
In 2015, 20 boxes were occupied – 8 Swallow, 9 Sparrow, 3 Chickadee, 11 empty.
In 2016, 23 boxes were occupied – 9 Swallow, 10 Sparrow, 2 Chickadee, 2 double (Swallow/Sparrow), 6 empty.